Cisco IOS Cookbook, 2nd Edition

Tunneling Foreign Protocols in IP

Problem

You want to tunnel a foreign protocol such as IPX traffic through your IP network.

Solution

One of the most important applications of tunnels is for passing foreign protocols through a network that only supports IP. A typical example of this would be IPX, although the configuration is similar for other protocols such as Appletalk:

Router1#configure terminal 
Enter configuration commands, one per line.  End with CNTL/Z.
Router1(config)#ipx routing AAAA.BBBB.0001
Router1(config)#interface Tunnel1
Router1(config-if)#ipx network AAA
Router1(config-if)#tunnel source 172.25.1.5
Router1(config-if)#tunnel destination 172.25.1.7
Router1(config-if)#exit
Router1(config)#end
Router1#

Then on the other router you must create a tunnel interface with a matching source and destination, as well as a matching IPX network number:

Router5#configure terminal 
Enter configuration commands, one per line.  End with CNTL/Z.
Router2(config)#ipx routing AAAA.BBBB.0002
Router5(config)#interface Tunnel3
Router5(config-if)#ipx network AAA
Router5(config-if)#tunnel source 172.25.1.7
Router5(config-if)#tunnel destination 172.25.1.5
Router5(config-if)#exit
Router5(config)#end
Router5#

Discussion

This recipe is nearly identical to Recipe 12.1, but instead of tunneling IP traffic through an IP network, we use the same kind of tunnel to pass IPX traffic through the same network. Note that of all the supported tunnel modes mentioned in Table 12.1, only the default GRE will transport ...